At present car components are washed at a first station with low pressure water at 80-120 psi and the washed components are then passed to a drying station where air is usually blown at the components. Each station has a wheel assembly around which a component passes so that a continuous cycle can be achieved whilst the components are retained at each station a sufficiently long time to complete the washing or drying step respectively. In order to supply the water manifold or manifolds of previous arrangements a very high powered pump was required in order to enable sufficient flow to be generated.
The present apparatus suffers from the disadvantages that (a) the washing and drying stages are slow requiring the wheel arrangements at each station and (b) that as low pressure water is used about 1000-1200 gallons per minute of dirty water is produced creating filtration problems. The main filtration at present is effected by blanket filters in which a vacuum draws off swarf etc. However very soon the filters become blocked and the washing water is recycled and re-used still dirty.
Examples of conventional engine block cleaning apparatus are U.S. Pat. Nos. 2,979,062, 3,153,419 and 2,972,995. U.S. Pat. No. 2,979,062 discloses washing apparatus for engine blocks having a washing stage, a rinsing stage and a drying stage. Each stage includes a respective, vertically-disposed turret about which the block passes during movement from one end of the apparatus to the other. The components are washed with `high pressure` water from fixed spray nozzles but the nature of the pump required suggests that `high pressure` is not within the ranges specified in the present application. Moreover there is no control of the supply of water to the respective nozzles.
U.S. Pat. No. 3,153,419 discloses a similar arrangement but the turrets are arranged horizontally. The component is washed with water which is pumped from a reservoir by means of a pump capable of delivering 1500 gallons per minute at a pressure of 70 psi which is regarded in that specification as "high pressure washing".
U.S. Pat. No. 2,972,995 discloses apparatus for washing engine blocks in which the engine blocks are passed along a conveyor path and washed by a series of fixed jets with water under `substantial` pressure.
The use of water at high pressure for cleaning has been proposed before but in these prior arrangements the requirements have not been the same. For example U.S. Pat. No. 4,027,687 discloses a method of cleaning the surface of silicon semiconductor material using water at 4000-6000 psi, and in U.K. specification 1,386,342 there is disclosed a system of washing aluminium foils with high pressure water up to a pressure of about 2844 psi; however in neither of these two arrangements is the quantity of water used going to be a serious consideration.
Similarly, U.S. Pat. No. 3,060,064 relates to the cleaning of tube bundles which includes a final step of jetting water at 1000 to 3000 psi, but there is no suggestion that the water is to be collected and reused and accordingly the quantity and control of the amount of water consumed is unlikely to be important.
In the present invention by controlling the application of the water via the washing jets the amount of water consumed is reduced to a minimum having the advantage that a smaller pump can be used and filtration for recycling of dirty water is simpler.